Since an oil filter is applied with a thin film of oil rubbed on its seal, I think everyone can be forgiven for failing to notice an occasion where the gasket remains stuck to the block. It shouldn't have, but did. Having had the problem myself with a car 25 years ago, I have always remembered to look for the old gasket when the time comes around again. It did, 1 year ago. I was paying attention and caught it. Ah! nothing like experience!

Good point, Flogge. Since the effect of an oil spill can be so devastating, you have to wonder whether there is a design that could prevent oil leakage from reaching tires. If the racing bikes can do it, perhaps street bikes could as well.

The rules of most motorcycle racing leagues require the bodywork under the engine to act as a catch pan for leaking oil. This is mainly to prevent oil spilling on the track which can cause accidents if it accumulates. They also have banned any coolants besides straight water. Ethylene glycol is very difficult things to clean from a road surface completely.

I've always been told to inspect the sealing surfaces prior to re-assembly. At the very least take a glance at the old filter and make sure it is intact.

Might not be "made" by monkeys, but posting it here might prevent some "monkey-ish" tendencies in others. Next time I change my oil, I'm going to start looking at that myself. I never would have thought to check it. Thanks for posting!

That reminds me of a favorite trick that I used many times to remove very stuck theaded plugs from the engine blocks when rebuilding them: Take a small propane torch and softly heat both the stuck plug and the surrounding area of the monobloc, just enough to get it hot, but nothing more. Then quickly spray penetrating oil with the thin plastic tube mounted on the spray nozzle, directing the penetrating oil or WD-40 EXACTLY to the edge of the threads, strongly cooling the plug... the repentine contraction usually breaks the bond and allows one to easily unscrew the plug out, instead of trying to use brute force and completely round the square hole in the plug and damaguing the tool at the same time!

Sorry Rob... but it has quite a bit of 'Monkey Design' indeed: Who can claim that a defective or damaged filter will NOT leak EVER???

A truly good design would avoid placing the filter (or any other part that contains oil) just in front of the rear wheel of the motorcycle. PERIOD!

And if anyone dares to say that the typical motorcycle layout with its space and size constraints has to place the oil filter ONLY in that place, a simple solution wasstill available: just place a sheet metal "catch pan" with a tubing line to divert any oil dripping AWAY from the rear tire! (That would be called a truly failproof design! :)

The VERY fortunate couple was extremely lucky to end up in one piece after that scary drive! (I can easily see from here the big smile of the driver and hear his presumptuous tale narration, saying something like this: "...But thanks to my huge motorcycle handling capabilities, I was able to regain the control, even with the rear tyre completely covered in top quality, very slippery Synthetic oil" :)

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